#include <iostream>
using namespace std;
const int N = 1e6 + 100;
long long a[N], n, lst[60], f[N];
int main() {
	scanf ("%lld", &n);
	for (int i = 1; i <= n; i++) scanf ("%lld", a + i);
	for (int i = 1; i <= n; i++) {
		f[i] = f[i - 1] + a[i - 1] & a[i];
		for (int j = 0; j < 60; j++) f[i] = max(f[i], f[lst[j]] + a[lst[j]] & a[i]);
		long long t = a[i], s = 0;
		while (t) t >>= 1, s++;
		lst[s] = i;
	}
	printf("%lld", f[n]);
	return 0;
}